17 replies to this topic

[Nick Warwick]

I am at the stage of shimming my diff, but i am getting a bit lost with it.

I put the diff in place and push it to the right (clutch side) and then i place the casing on and tighten that down. Then i put the output plate on the right hand side with a gasket and nip it up, next i am putting the left hand plate on without a gasket and nipping that up but i get no gap at all to get a feeler gauge in.

Am i going wrong somewhere? When i removed the old diff it came with 0.12thou of shims already in.

Cheers
Nick

[Dan]

How tight have you got the diff case? The diff needs to be able to slide. Remember if the diff case is a gasket type you will need gaskets fitted as even with it a little loose, without gaskets it will be pinching the bearings.

[Nick Warwick]

I was told that it shouldn't have a gasket on the diff casing because when i removed it their was no gasket. I did tighten it up more than the output plates.
Should it just be finger tight?

I am just worried i wont get this right.

[Dan]

Yes casings are either designed for a gasket or not, if it didn't have any then you don't need them.

The casing shouldn't be fully tight for this no, it needs to be in the right position for the side plates to align but not fully tight. If the diff can't move, you can't shim it. Also if it can't move and you fully torque the side plates with it in the wrong position you can deform the plates.

[Nick Warwick]

right so if the diff is unable to move side to side i need to let the case off more?

[Sheikh Pip]

Search for this on U-tube, I'm sure our Mr Guessworks has a video on there explaining all you need to know!

[AndyMiniMad.]

Take a look at this..note I have the gaskets fitted on the side plate and the bolts nipped up..I did not need gaskets on the actual diff cover..

http://www.theminifo...ng/page__st__15

[Nick Warwick]

Just watched the Guesswork video. Thats made things a lot clearer for me now, but it looks like i'm going to need a few more shims!

[Nick Warwick]

just measured the gap between the bearing and output plate and it was 0.015" but i dont know what the gasket is because i have nothing to measure it with.

so if i take the gasket is a 0.003 like andys is, i have 0.012" of shims so the gasket will make up the extra 0.003" i need. correct?

confusing me haha

[Nick Warwick]

crap im going to need another 0.004" shim arn't i because of the bearing

[dklawson]

The only thing I can add is to NOT assume anything about the thickness of the output flange gaskets. You will need the ones you plan on using and you will have to measure their thickness after they have been tightened once to compress them. Do not go by the simplified math in the older Haynes manuals to determine the shims. The older Haynes manuals assumed a certain compressed flange gasket thickness. The gaskets available today are much thicker than the ones Haynes anticipated. In short, "measure twice, cut once" when selecting the shims.

[Nick Warwick]

I am stuck then unless somebody knows the compressed size of the black output gasket from minispares

[AndyMiniMad.]

Measure it with a micrometer...They are around £8 for the digital ones..ive used mine loads..

[tiger99]

Generally, when measuring the thickness of any gasket on any car (where it is necessary) there is often a notch in the outer edge of the gasket, where you can insert the tip of a feeler gauge between the mating surfaces. If the gaskets are not notched, you can carefully cut notches in places where there is plenty of width, so you don't spoil the sealing capabilities. You might want three of four notches, well spread, to ensure that the mating faces are pulled down evenly.

Use of the feeler gauges gives you the compressed thickness, which is usually what matters.

[Spitz]

I've never really understood how to do it properly.....I admit.
Even after watching guessworks video......brain fart.
I think I put too many shims in mine last year, as I get some toque steeer now that I didn't before ( or maybe that means too few?? )